Canon InkTanks and the Notorious Air in tube issue

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I'm sceptical that it's some kind of damage that's causing this issue. All three of my Canon tanks have done it. Different models, different heads, different ink processes, etc. And they all do it. I'm inclined to believe it's a design flaw.

Full disclosure I've only had 5 different MegaTank printers and 2 of those have never been even turned on so I don't have the same breadth of experience of you but I'd be inclined to agree that their system is flawed. The question is whether or not it can be fixed.

Canon's bad about stocking replacement heads in their store and every other option is massively overpriced. I suppose if I get into production work soon I'll have new heads ordered to have on-hand spares. But even then it's not worth replacing a working head for a problem that seems universal and can be fixed with maintenance prints. (Which I have to do anyway to stop wasteful auto-cleaning.)

On this I'm going to disagree. Any air ingress into a CIS system (whether it's Canons MegaTank, Epson Ecotank or some third party installation) is a bad thing and should not be happening, particularly for one that is designed into the printer by the manufacturer.

Coming back to the. How do we fix it?... To my way of thinking the problem is likely to be a poor seal between the printhead inlets and the carriage lids but the interface between the two is overly complex and doesn't lend itself to a simple fix like a gasket. Looking closely at the ink outlet (in the carriage lids) the seal seems to be internal so any crud that gets in there will allow air ingress and pigment black seems the most likely to create that kind of detritus. I wonder if there's any mileage in trying to flush the outlet hole gently with some cleaning solution via a thin needle and syringe (with a sponge or absorbent material underneath to catch the fluid). Hasten to add I don't mean sealing the needle against the outlet but just sort of jet washing it just around inside that outlet port.

Thoughts?

 

[brwinters]

Full disclosure I've only had 5 different MegaTank printers and 2 of those have never been even turned on so I don't have the same breadth of experience of you but I'd be inclined to agree that their system is flawed. The question is whether or not it can be fixed.

On this I'm going to disagree. Any air ingress into a CIS system (whether it's Canons MegaTank, Epson Ecotank or some third party installation) is a bad thing and should not be happening, particularly for one that is designed into the printer by the manufacturer.

Coming back to the. How do we fix it?... To my way of thinking the problem is likely to be a poor seal between the printhead inlets and the carriage lids but the interface between the two is overly complex and doesn't lend itself to a simple fix like a gasket. Looking closely at the ink outlet (in the carriage lids) the seal seems to be internal so any crud that gets in there will allow air ingress and pigment black seems the most likely to create that kind of detritus. I wonder if there's any mileage in trying to flush the outlet hole gently with some cleaning solution via a thin needle and syringe (with a sponge or absorbent material underneath to catch the fluid). Hasten to add I don't mean sealing the needle against the outlet but just sort of jet washing it just around inside that outlet port.

Thoughts?

I agree air ingress is bad, don't get me wrong. I'm just saying that for me personally, my maintenance routine solves it enough where head replacements aren't worth the expense (and I don't think it would ultimately fix it).

You could be right on that gasket comment. My guess is either that or the capping station. However, my iP100 that's far older and gets thrown around in my backpack and not used for a week at a time... That never has clogged once, using either the OEM 35 and 36 carts or those OEM carts filled with Canon OEM ink from tank bottles. That does point at the gasket perhaps being the issue.

Again it just comes down to running a cleaning print every day, which I already do, band-aiding the issue well enough that it's not worth poking around yet. Too expensive of kit to prod around in the valves and seals and risking damage, considering how easy it is to keep it running by printing regularly. (And this comes from the guy that retrofits removable waste tanks onto his printers.)

Maybe someday if I get the chance to play around with it, I'll experiment some. Tanks are just too pricey to experiment on and I don't tend to see them go for cheap even used.

 

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I agree air ingress is bad, don't get me wrong. I'm just saying that for me personally, my maintenance routine solves it enough where head replacements aren't worth the expense (and I don't think it would ultimately fix it).

My only concern there is that you're getting air ingress into the printhead that, over time will ultimately kill the nozzles due to lack of ink/coolant. But as the expression goes "If it ain't broke, don't fix it".

Maybe someday if I get the chance to play around with it, I'll experiment some. Tanks are just too pricey to experiment on and I don't tend to see them go for cheap even used.

Keep me posted if you do decide to delve into the innards. I'll do the same if I get the opportunity to grab a unit that's can act as a donor unit or has the same problem for me to mess with.

 

[brwinters]

My only concern there is that you're getting air ingress into the printhead that, over time will ultimately kill the nozzles due to lack of ink/coolant. But as the expression goes "If it ain't broke, don't fix it".


Keep me posted if you do decide to delve into the innards. I'll do the same if I get the opportunity to grab a unit that's can act as a donor unit or has the same problem for me to mess with.

In theory that print head shouldn't be at risk of dying, because anytime air does get in the line, I do a heavy cleaning cycle until it's out. And I never wind up with air in the lines if I keep doing that maintenance print regularly. Same behavior across the board, all the way up to my pro 2000.

I do wonder sometimes if there could potentially be a pocket of air in the head though.

 

[websnail]

In theory that print head shouldn't be at risk of dying, because anytime air does get in the line, I do a heavy cleaning cycle until it's out. And I never wind up with air in the lines if I keep doing that maintenance print regularly. Same behavior across the board, all the way up to my pro 2000.

I guess I'm something of a perfectionist to a degree. I don't get why a printer should need you to waste so much ink on power cleans, etc... just because someone didn't design the head-inlet to ink feed interface properly.

I do wonder sometimes if there could potentially be a pocket of air in the head though.

It's possible I suppose but you could only really rule that out by putting in new printheads and watching it like a hawk...

Either way, thanks for the info... I'll update if I develop any other information my end.

 

[brwinters]

I guess I'm something of a perfectionist to a degree. I don't get why a printer should need you to waste so much ink on power cleans, etc... just because someone didn't design the head-inlet to ink feed interface properly.

I don't have to do much for power cleaning. Once every few weeks maybe. Which is low enough to write off as regular cleaning imo. Daily maintenance prints stop me needing to do any cleaning most of the time, including the automatic idle timer cleanings. But I get what you mean.

 

[James Mike]

I wonder if this problem starts to occur after a certain amount of pages printed or as the printer ages which could suggest that the carriage port/cartridge inlet is loosing its shape and seal.

 

[brwinters]

I wonder if this problem starts to occur after a certain amount of pages printed or as the printer ages which could suggest that the carriage port/cartridge inlet is loosing its shape and seal.

It seems pretty instant in my experience. The biggest single factor in air uptake has always been disuse for all three of my tanks. Right out of the box up till after 1000 pages and onward

 

[James Mike]

It seems pretty instant in my experience. The biggest single factor in air uptake has always been disuse for all three of my tanks. Right out of the box up till after 1000 pages and onward

Does ink level affect how fast air uptake forms when the printer sits unused? Does it occur far more readily before or after the 1000 pages mark?

Not sure if its related but our G3010 seemed to have sucked ink from main ink tank towards its airbalance/buffer chambers somewhere around that 1000 pages mark after doing full page heavy color prints (the ink levels did not decrease at the same rate with similar print jobs after refilling just above half to full).

 

[brwinters]

Does ink level affect how fast air uptake forms when the printer sits unused? Does it occur far more readily before or after the 1000 pages mark?

Not sure if its related but our G3010 seemed to have sucked ink from main ink tank towards its airbalance/buffer chambers somewhere around that 1000 pages mark after doing full page heavy color prints (the ink levels did not decrease at the same rate with similar print jobs after refilling just above half to full).

Not 100% sure but it seems pretty arbitrary. The ink will also stick to the walls of the tank during use because of surface tension so that may affect how you perceive the levels changing.

I haven't fully disassembled one of these machines yet but I would assume there is something to force ink down the line while printing?